The goal of this proposal is to bring a BIAcore 3000 biosensor to the Wayne State University. This instrument, designed to detect, monitor, and quantify biomolecular interactions, will be a significant asset to the research programs of a number of NIH-funded investigators at this institution. At present, there is no biosensor available at Wayne State nor anywhere else in metropolitan Detroit. The instrument will be of great benefit to the applicants in a variety of ongoing projects including i. an examination of the interactions among proteins involved in peroxisome biogenesis, ii. a quantification of estrogen receptor (and mutated estrogen receptor)-.coregulator interactions, iii. a characterization of the interactions of cathepsins and extra-cellular matrix proteins in the context of proteolytic cascades which occur on the tumor cell surface, iv. a molecular description of how the estrogen receptor binds specific protein, DNA, and attenuated estrogen ligands, v. an examination of how the aryl hydrocarbon receptor binds the retinoblastoma tumor suppressor protein and mediates cell cycle control, and vi. an analysis of the interactions of matrix metalloproteinases and their inhibitors, called TIMPS, in cancer. Wayne State University is strongly committed to this proposal. Through the contributions of 19 investigators, the School of Medicine, and the University at large, the following have been secured: 1. A funded long-term plan for maintenance and continued operation of the BIAcore 3000 biosensor. 2. A centrally located core facility to house the equipment. 3. A funded technician who will be trained to operate and schedule usage of the instrument. The BIAcore 3000 biosensor is a state-of-the-art instrument that will provide extremely reliable data for years to come. The plan outlined herein will maximize efficient use of this instrument.